Skin Temperature Measurements Research Articles

Intraoperative Patient Warming Instead of Gas on the Management of Postoperative Pain in Laparoscopic Colectomy and Cholecystectomy: A Randomized Controlled Trial.

Blurred lines remain in details of the association between patient warming with postoperative pain and a proper analgesic requirement. Therefore, the present study proposes to observe the effects of intraoperative patient warming and carbon dioxide insufflation duration in laparoscopic colectomy (LCol) andlaparoscopic cholecystectomy (LChol) procedures on postoperative pain, analgesic requirements, and hemodynamics. The present study involved 80 cases aged 18-80 years with the American Society of Anesthesiologists I-III classification, possessing two initial groups primarily, one for LCol and one for LChol. Subsequently, each was divided into two through randomization for intraoperative warming. Postoperatively, pain perception, per se, was evaluated using the visual analog scale (VAS) score at the 30 minutes, 1st, 6th, 12th, and 24th hours, along with the impact of pain on hemodynamic parameters and side effects such as nausea/vomiting and the dosage of analgesics used. Groups actively heated with warm air-blowing devices detected significantly higher intraoperative core and skin temperature measurements, and postoperative early pain perception was significantly lower in the warmed ones. Furthermore, a significant decrease in the VAS scores and the analgesic at the 12th and 24th hours compared to the first six hours was recognized between them. Consequently, herewith, we postulate that so-called patient warming positively affects the VAS scores.

Radiative Thermal Management in Face Masks with a Micro/Nanofibrous Filter.

Micro/nanofiber-based face masks are recommended as personal protective equipment (PPE) against particulate matter (PM), especially PM0.3. Ensuring thermal comfort in daily use face masks is essential in many situations. Here, radiative thermal management is introduced into face masks to elevate the user comfort. An interlayered poly(lactic acid) (PLA) micro/nanofibrous filter effectively captures PM0.3 (99.69%) with minimal pressure drop (49 Pa). Thermal regulation is accomplished by controlling the mid-infrared (MIR) emissivity of the face mask's outer surface. Cooling face masks feature cotton nonwovens with high MIR emissivity (90.7%) for heat dissipation, while warming face masks utilize perforated Al/PE films with minimal MIR emissivity (10.7%) for warmth retention. Skin temperature measurements indicate that the skin covered by the cooling face mask could be 1.1 °C lower than that covered by the 3M face mask, while the skin covered by the warming face mask could be 1.3 °C higher than that covered by the 3M face mask.

Contact measurement of skin temperature using a wearable two-channel PPG optical sensor supplemented by thermometers

Abstract This paper describes realization, basic properties, testing, and experiments with a special prototype of a wearable two-channel photoplethysmography (PPG) sensor supplemented by contact thermometers that maps the skin temperature at the place where the optical part of the sensor touches a measured hand part (typically a wrist and fingers). Preliminary measurement confirms that proposed I2C thermometers have proper stability and precision, so can be successfully used in the developed PPG sensor. The performed main experiments show that the significant increase of temperature was always observed at the place of the worn PPG sensors during the whole measurement. This rise of temperature affects mainly the PPG signal range, thus it has also influence on the quality of the sensed PPG wave. The conclusion formulates the final recommendation about the necessity of at least 5-minute time delay between the PPG sensor placement on the hand and the start of the PPG signal acquisition. While the current measurements were realized in normal laboratory conditions, the whole wearable PPG sensor consists of non-ferromagnetic materials and all parts are fully shielded by aluminum boxes to enable measurement in a low magnetic field environment which, is our final long term research aim.

Skin temperature measurement based on diffuse reflection light at scattering variation independent source-detector separation

This study presents a method for predicting skin temperature using near-infrared light at 1314 nm and 1409 nm wavelengths. Skin temperature is a critical factor in the precision of in vivo optical measurements, necessitating accurate determination. Our approach detects temperature-induced tissue absorption changes, utilizing absorbance variations at specific scattering independent source-detector separations (SVI-SDSs) to estimate temperature. The 1409 nm wavelength is the main indicator for temperature prediction, with the 1314 nm wavelength used to identify the SVI-SDS for the 1409 nm light. Experimental data from four subjects were collected using an optical sensor across five SDSs ranging from 0.9 mm to 2.3 mm. We identified the SVI-SDS for the 1409 nm light at approximately 2.3 mm, where absorbance exhibited the most sensitivity to temperature changes, resulting in the lowest root mean square error (RMSE) and highest temperature sensitivity. These findings offer a valuable reference for the real-time monitoring and calibration of in vivo skin temperature, enhancing the accuracy of optical measurement techniques.

Influences of Indoor Air Temperatures on Empathy and Positive Affect.

The consequences of climate change are already visible, and yet, its effect on psychosocial factors, including the expression of empathy, affect, and social disconnection, is widely unknown. Outdoor conditions are expected to influence indoor conditions. Therefore, the aim of this study was to investigate the effect of indoor air temperature during work hours on empathy, positive and negative affect, and social disconnection. Participants (N = 31) were exposed, in a cross-over design, to two thermal conditions in a simulated office environment. Questions on empathy and social disconnection were administered before and after the exposure to each condition, while affect was measured throughout the day. Subjective thermal sensation and objective measures of mean skin temperature were considered. The results indicated a significant difference in empathy (F(1, 24) = 5.37, p = 0.03, with an η2 = 0.126) between conditions. Participants reported increases in empathy after exposure to the warm condition compared to the cool condition, in which reductions in empathy were reported. Although the same pattern was observed for positive affect, the difference was smaller and the results were not significant. Thermal sensation had a significant effect on changes in empathy too (F(1, 54) = 7.015, p = 0.01, with an R2 = 0.115), while mean skin temperature had no effect on empathy (F(1, 6) = 0.53, p = 0.89, with an R2 = 0.81). No effects were observed for positive and negative affect and social disconnection. Longitudinal studies are needed to support these findings.

Hot, cold, or just right? An infrared biometric sensor to improve occupant comfort and reduce overcooling in buildings via closed-loop control

To improve occupant comfort and save energy in buildings, we have developed a closed-loop air conditioning (AC) sensor-controller that predicts occupant thermal sensation from the thermographic measurement of skin temperature distribution, then uses this information to reduce overcooling (cooling-energy overuse that discomforts occupants) by regulating AC output. Taking measures to protect privacy, it combines thermal-infrared (TIR) and color (visible spectrum) cameras with machine vision to measure the skin-surface temperature profile. Since the human thermoregulation system uses skin blood flow to maintain thermoneutrality, the distribution of skin temperature can be used to predict warm, neutral, and cool thermal states. We conducted a series of human-subject thermal-sensation trials in cold-to-hot environments, measuring skin temperatures and recording thermal sensation votes. We then trained random-forest classification machine-learning models (classifiers) to estimate thermal sensation from skin temperatures or skin-temperature differences. The estimated thermal sensation was input to a proportional integral (PI) control algorithm for the AC, targeting a sensation level between neutral and warm. Our sensor-controller includes a sensor assembly, server software, and client software. The server software orients the cameras and transmits images to the client software, which in turn assesses occupant skin temperature distribution, estimates occupant thermal sensation, and controls AC operation. A demonstration conducted in a conference room in an office building near Houston, TX showed that our system reduced overcooling, decreasing AC load by 42% when the room was occupied while improving occupant comfort (fraction of “comfortable” votes) by 15 percentage points.

Enhanced conductive body heat loss during sleep increases slow-wave sleep and calms the heart

Substantial evidence suggests that the circadian decline of core body temperature (CBT) triggers the initiation of human sleep, with CBT continuing to decrease during sleep. Although the connection between habitual sleep and CBT patterns is established, the impact of external body cooling on sleep remains poorly understood. The main aim of the present study is to show whether a decline in body temperatures during sleep can be related to an increase in slow wave sleep (N3). This three-center study on 72 individuals of varying age, sex, and BMI used an identical type of a high-heat capacity mattress as a reproducible, non-disturbing way of body cooling, accompanied by measurements of CBT and proximal back skin temperatures, heart rate and sleep (polysomnography). The main findings were an increase in nocturnal sleep stage N3 (7.5 ± 21.6 min/7.5 h, mean ± SD; p = 0.0038) and a decrease in heart rate (− 2.36 ± 1.08 bpm, mean ± SD; p < 0.0001); sleep stage REM did not change (p = 0.3564). Subjects with a greater degree of body cooling exhibited a significant increase in nocturnal N3 and a decrease in REM sleep, mainly in the second part of the night. In addition, these subjects showed a phase advance in the NREM-REM sleep cycle distribution of N3 and REM. Both effects were significantly associated with increased conductive inner heat transfer, indicated by an increased CBT- proximal back skin temperature -gradient, rather than with changes in CBT itself. Our findings reveal a previously far disregarded mechanism in sleep research that has potential therapeutic implications: Conductive body cooling during sleep is a reliable method for promoting N3 and reducing heart rate.

Physiological and Thermal Sensation Responses to Severe Cold Exposure (−20 °C)

Various jobs, indoors and outdoors, are subjected to severe cold temperatures during daily activities. Extremely low-temperature exposure and work intensity affect health, safety, and occupational performance. This work aimed to assess the physiological and thermal sensation responses before, during, and following a 60 min exposure to cold (−20 °C), during which occupational activities were developed. Using ingestible telemetric temperature pills, eight skin temperature sensors, blood pressure equipment, and the Thermal Sensation Questionnaire, experiments were conducted with 11 healthy male volunteers wearing highly insulating cold protective clothing. The most notorious alterations were reported in mean skin temperatures and thermal sensation responses during the first 20 min of cold exposure. Among the eight skin temperature points, the forehead and left hand showed a higher sensitivity to cold. The mean core temperature reported significant variations throughout the protocol, with decreases during the initial 10 min of cold exposure and posterior increases despite the cold environment. Blood pressure showed slight increases from the initial to the recovery period. Overall, outcomes contribute to current scientific knowledge on physiological and perception responses in extremely cold environments while describing the influence of protective clothing and occupational activities on these responses. Future research should be developed with additional skin temperature measurements in the extremities (fingers, face, and toes) and the analysis of thermal sensation potential associations with performance changes, which can also be of great significance for future thermal comfort models.

Assessing the thermal risks for residents and visitors in traditional Street-facing Dwellings with Eaves Gallery during an extreme heatwave event

Street-facing Dwelling with Eaves Gallery (SDEG) was built for both commercial activities and residential needs. The Eaves Gallery (EG) and courtyards with small sky view factor (SVF) in those dwellings were shaped to prevent the residences or pedestrians from strong sun radiation, heavy rain, or snow. As a climate-adaptive vernacular architecture, it has lasted for hundreds of years in the large areas along the Yangtze River Basin (YRB) of China. Yet, few studies systematically investigate the thermal conditions of these dwellings and validate their climate resilience quantitatively under heat waves. Concerning the extreme weather caused by climate change, this study investigated indoor, semi-outdoor, and outdoor thermal comfort (OTC) of the SDEG in Xiaohe Town of Hubei province, China during the heatwave event in 2022. While mobile and fixed measurements were carried out to capture the data of thermal environments, the skin temperature measurements were implemented to understand the thermal responses of the households. The results found that SDEG was qualified to help indoor households avoid the heat risk with proper thermal behaviors but cannot provide a safe thermal environment for the pedestrians in the semi-outdoor or outdoor space of the EG street throughout the day. This study demonstrated the negative effects of heatwaves on not only the walking visitors but also the livelihood of the residents, which is an appeal to scholars to attention to the heat risks and thermal behaviors of marginalized groups living in various vernacular buildings within the context of high-temperature scenarios under the heatwave conditions.

Radiative cooling face mask based on mixed micro- and nanofibrous fabric

A type of personal protective face mask with thermal comfort function is developed based on the radiative cooling concept. We show that the cooling face mask, with the combination of PLA meltblown microfibers and a thin sheet of mixed electrospun micro- and nanofibers as filtration media and a silk fabric as inner supporting layer, can provide high reflectivity (>85 %) in the solar spectrum and high emissivity (>96 %) in the atmospheric window. Outdoor measurement of simulated skin temperature demonstrates the skin covered by our cooling mask could be ∼ 2.7℃ lower than that covered by commercial 3 M N95 mask. Our cooling mask exhibits excellent filtration performance with 99.98 % filtration efficiency and < 110 Pa pressure drop because of the reduced stacking density of the filtration media. This research has the potential of developing thermal management textiles.

Temperature Differences Between Controlled Primary Hypothyroidism and Healthy Patients: An Exploratory Study.

Hypothyroidism is conventionally treated with replacement therapy through levothyroxine (LT4). Despite the improvement in symptoms, cold intolerance persists in some patients. The present study aims to determine whether there is a difference in temperature perception and skin temperature between patients with primary controlled hypothyroidism (PCH) and a group of healthy controls matched for body mass index and age. Secondarily we aimed to determine difference in quality of life. Skin temperature measurements were performed in both groups, both in the central and peripheral regions of the body. In addition, subjects were asked about their perception of temperature in a temperature-controlled room; anthropometric measurements were taken, their quality of life was assessed using the ThyPRO-39, and a thyroid hormone profile was performed. Eleven patients in the PCH group and 30 patients in the control group were studied. It was found that the group with PCH presented a significantly lower palmar temperature than the control group [mean (SD) of 32.05 (1.79) vs 33.10 (1.30) oC, P = .046]. A mediation model showed a direct effect. Temperature perception was equal between groups. The median (interquartile range) of ThyPRO was 8 (5.2) points in the control group vs 21.8 (13.5) in the group of controlled hypothyroidism, P < .001. These results suggest that, despite LT4 treatment, patients continue to present abnormalities in thermogenesis-related thermogenesis, and this may be due to a lack of hormonal adaptation to environmental changes and physiological demands, leading to lower body temperatures and increased sensitivity to cold.

Observational study of peripheral skin temperature changes following spinal anaesthesia for caesarean birth

BackgroundSpinal anaesthesia is widely used in obstetric anaesthesia practice but there is limited knowledge about the development of sympathetic blockade following spinal anaesthesia for caesarean birth. This study investigated the characteristics of sympathetic blockade by measuring peripheral skin temperature changes in the feet of patients given spinal anaesthesia for elective caesarean birth. MethodsA prospective observational study was conducted involving 60 eligible parturients scheduled for elective caesarean birth with spinal anaesthesia. Skin temperature probes were attached to the dorsum of both feet, and temperature measurements were recorded every minute. The dose of spinal anaesthesia given, and other relevant patient data, were collected. ResultsAll participants had successful spinal anaesthesia. Following spinal anaesthesia, a sustained rise in skin temperature of both feet was observed, indicating the presence of sympathetic blockade. The maximum rate of temperature increase occurred between 6 and 15 min after the intrathecal injection and plateaued from 22 min after the injection. Control participants did not show any changes in foot temperature. ConclusionsThis study demonstrates that successful spinal anaesthesia for caesarean birth results in a consistent and reliable rise in skin temperature of the feet that is evident after six minutes from intrathecal injection. The observed temperature changes provide indirect objective evidence of bilateral sympathetic blockade. Measurement of feet skin temperatures may serve as an additional objective indicator of successful spinal anaesthesia, along with tests of lower limb motor block and sensory block height. These findings contribute to the understanding of sympathetic blockade during spinal anaesthesia.

Temperature assessment in newborn: a better method

Background: Accurate temperature assessment is essential in neonatal care as minor temperature changes can have a significant impact on the health and well-being of newborns. The purpose of this study was to compare the performance of three different types of thermometers, including non-contact infrared, digital, and mercury thermometers, for temperature assessment in newborns. Methods: This was a prospective, comparative study conducted between April 2022 and August 2022 in Cheluvamba hospital, Mysuru. A total of 400 healthy newborns were included in the study. Temperature readings were taken from the mid-forehead non-contact infrared thermometer and axilla using digital and mercury thermometers, while maintaining aseptic precautions. Parental oral consent was obtained for participation. Results: The mean temperature recorded with the digital thermometer in the axilla was statistically higher than that recorded with the mercury thermometer. The non-contact infrared thermometer showed a strong positive correlation with the mercury thermometer for the axilla region. Conclusions: The digital thermometer is a useful device for easy and valid measurement of skin temperature in newborns, especially when applied to the axilla. The findings suggest that the use of digital thermometers for axillary temperature measurement in neonates is supported by previous studies, which have reported their accuracy and reliability in comparison to mercury thermometers. The non-contact infrared thermometer may have limitations and its accuracy may vary depending on the site of measurement. The use of digital thermometers for neonatal temperature measurement may be more convenient, less hazardous, and equally reliable compared to traditional mercury thermometers.

Heat loss or heat uptake? Skin temperature in Antillean manatees (Trichechus manatus manatus, Sirenia: Trichechidae) in Belize

Introduction: The two subspecies of the West Indian manatee (Trichechus manatus), Florida manatees (T. m. latirostris) and Antillean manatees (T. m. manatus), face different environmental challenges. While Florida manatees have to cope with winter water temperatures below their lower critical temperature of ~ 20 °C and air temperatures below freezing, Antillean manatees live in year-round warm Caribbean waters. Sirenians lack effective thermal insulation and have limited capability of controlling peripheral heat loss. Although severe cold related health issues and mortality are primarily known in Florida manatees, it can be assumed that Antillean manatees and other extant sirenians share the cold-sensitivity, but hardly ever experience it. Contrarily, during summer, Antillean manatees may face the opposite form of thermal stress by being exposed to water temperatures close to their body temperature. However, the upper critical temperature of manatees is not known.&#x0D; Objective: To improve understanding of the impact of high ambient temperatures on manatee physiology.&#x0D; Methods: We measured skin temperature in six Antillean manatees in two different habitats in Belize, and compared the results to skin temperatures measured in two captive Florida manatees.&#x0D; Results: We found a similar temperature distribution pattern over the body surface in both subspecies, but significantly higher temperatures and larger temperature ranges among measuring points in Antillean manatees as compared to Florida manatees. In one Antillean manatee, skin temperature was consistently lower than ambient water temperature by up to 2.5 °C. This implies potential heat uptake from the environment, in contrast to the heat loss experienced by Florida manatees at low water temperatures, apparent in skin temperatures above ambient water temperature.&#x0D; Conclusions: Our findings suggest that heat stress may be a more likely risk for manatees in warm tropical waters. Despite the small sample size, our results present important findings towards understanding thermal tolerance and impact of high ambient temperatures on manatee physiology.

Development of an automatic personal comfort system (APCS) based on real-time thermal sensation prediction

Most existing building thermal environment design methods focus on the overall environment without considering individual demands, which can result in inadequate comfort and unnecessary energy consumption. To address individual differences, appropriate measures must be followed at the individual level. This study presents the development of an automatic personal comfort system (APCS) for regulating the local environment of individuals by integrating two personal thermal comfort technologies, personal comfort system (PCS) and personal comfort model (PCM). The equipment enables thermal sensation prediction through infrared skin temperature and environmental parameters measurements, which is used to regulate the corresponding PCS device. The proposed thermal sensation prediction model based on random forest can achieve a prediction accuracy of 69%, while the PCS control strategy comprehensively considers thermal sensation vote (TSV) and airflow acceptability. The APCS performance test experiment involved 25 male adult subjects. The results indicated that PCS operating states were consistent under both manual and automatic control conditions. Moreover, TSV remained within the neutral zone for most participants throughout the experiment. These findings demonstrate that the APCS realized good automatic operation to ensure the comfort of the personnel. The APCS framework holds reference value for research on personal thermal comfort and future thermal environment construction, extending beyond the equipment itself.

Hardware-in-the-loop setup for contactless skin servo control of neonatal incubators

Infant incubators are used to provide an optimal microclimate for premature infants who are thermally instable. Care in the incubator is stressful for the newborn, therefore, current research aims at establishing contact-free monitoring using infrared thermography, thus, improving comfort and reducing skin contact. The skin temperature can already be controlled automatically in current incubators by using adhesive temperature sensors, resulting in possible irritations and damages to the infant’s skin.In this work, a hardware-in-the-loop test bench was developed to test the interaction of all components necessary for skin temperature control with contactless skin temperature measurement. Accordingly, we designed a setup which can control the incubator, the contactless measurement setup, and a thermal neonate phantom. This offers the possibility to test skin temperature controllers immediately in a closed loop and easily simulate physiological and pathological scenarios.After setting up the test bench, the control systems considered were modeled and identified. Subsequently, initial controllers were designed and validated. We recalled that open incubator hand ports have long been considered a significant disturbance for temperature control. Hence, the performance of the current disturbance rejection in the given incubator setting was investigated. Subsequently, a change of the patient’s metabolism was simulated as a specific challenge.In our case, all controllers investigated were able to stabilize the skin temperature compared to the open-loop case. In the future, the presented hardware-in-the-loop concept will help to design and sufficiently validate skin temperature controllers for subsequent clinical trials.

Assessing the reliability of an infrared thermography protocol to assess cold-induced Brown Adipose Tissue activation in french psychology students

The authors use infrared thermography measurements of skin temperature to non-invasively assess the heat production of Brown Adipose Tissue (BAT). In species other than humans, BAT has been linked to maternal care, and may thus be crucial for understanding differences in attachment security. Whereas early BAT research measured its relative presence in the human body through radioactive tracers, researchers have recently used infrared thermography measurement of skin temperature in cold conditions to study BAT thermogenesis outside of medical facilities. Infrared thermography relies on comparing skin temperature in the supraclavicular region (where a BAT depot is located) with skin temperature in the sternal region (which contains no BAT depots) in cold conditions, when the supraclavicular BAT depot produces heat. We replicated an infrared thermography protocol, which previously reported an increase of 0.2 °C in supraclavicular (vs. sternal) skin temperature in cold (vs. control) conditions in only 7 adults, which probably led to overestimation of the effect. With a much larger sample size (N = 94 young adults) and a similar protocol, we did not find any significant variation in relative, Cohen’s d = 0.10, 95% CI [-0.31, 0.50], or absolute supraclavicular skin temperature, Cohen’s d = 0.11, 95% CI [-0.30, 0.52]. Using conditional random forests, we also excluded a variety of alternative explanations for why the method failed to achieve an effect. This protocol of infrared thermography cannot measure BAT thermogenesis and is thus not recommended for future studies to study individual differences in attachment.

Skin temperature as a predictor of on-the-road driving performance in people with central disorders of hypersomnolence.

Excessive daytime sleepiness is the core symptom of central disorders of hypersomnolence (CDH) and can directly impair driving performance. Sleepiness is reflected in relative alterations in distal and proximal skin temperature. Therefore, we examined the predictive value of skin temperature on driving performance. Distal and proximal skin temperature and their gradient (DPG) were continuously measured in 44 participants with narcolepsy type 1, narcolepsy type 2 or idiopathic hypersomnia during a standardised 1-h driving test. Driving performance was defined as the standard deviation of lateral position (SDLP) per 5 km segment (equivalent to 3 min of driving). Distal and proximal skin temperature and DPG measurements were averaged over each segment and changes over segments were calculated. Mixed-effect model analyses showed a strong, quadratic association between proximal skin temperature and SDLP (p < 0.001) and a linear association between DPG and SDLP (p < 0.021). Proximal skin temperature changes over 3 to 15 min were predictive for SDLP. Moreover, SDLP increased over time (0.34 cm/segment, p < 0.001) and was higher in men than in women (3.50 cm, p = 0.012). We conclude that proximal skin temperature is a promising predictor for real-time assessment of driving performance in people with CDH.

Effect of a Body Part Action on Body Perception of the Other Inactive Body Part

The rubber hand illusion (RHI) is an illusory experience in which a fake rubber hand is felt as if it were one’s own hand when the visible fake and invisible real hands are stimulated synchronously. Although several studies have suggested contributions of action to body ownership using the RHI paradigm, the relationship between body ownership and agency has not yet been fully revealed. To better understand this relationship, the present study investigated the transfer of body ownership between body parts induced by a body part action. Using an RHI paradigm involving virtual reality, we tested whether a simple finger action of the dominant (active) hand can induce the embodiment of a virtual hand corresponding to the non-dominant (inactive) hand. We evaluated the illusory experience, perceptual changes, and physiological changes during the experiment with a subjective questionnaire, crossmodal congruency effect measurement, and skin temperature measurement, respectively. The results demonstrated that the finger action induced the embodiment of both virtual hands, causing a significant increase in agency of the inactive hand. This suggests that the illusory experience induced by an active body part contributes to an increase in agency as well as body ownership over the virtual body of the other inactive body part.

Increases in local skin temperature correlate with spontaneous foot lifting and heat hyperalgesia in both incisional inflammatory models of pain.

This study investigated if a localized increase in skin temperature in rat models of incisional and inflammatory pain correlates with the intensity of spontaneous and evoked pain behaviors. Anesthetized rats received either a 20-mm longitudinal incision made through the skin, fascia, and muscle of the plantar hind paw or an injection of complete Freund adjuvant into the plantar hind paw of anesthetized rats to induce local inflammation. Spontaneous and evoked pain behaviors were assessed, and changes in skin temperature were measured using a noncontact infrared thermometer. There were no differences in skin temperature between the ipsilateral and contralateral hind paw before the incision or inflammation. Skin temperature increased at 2 hours after hind paw plantar incision or 1 day after inflammation of the affected paw, which gradually returned to baseline by the first day and fourth days after treatment, respectively. The increase in skin temperature correlated with the intensity of spontaneous pain behaviors and heat but not with mechanical allodynia. Our results suggest that a simple measurement of localized skin temperature using a noncontact infrared thermometer could measure the extent of spontaneous pain behaviors and heat hyperalgesia following plantar incision or inflammation in animals. In the absence of a reliable objective marker of pain, these results are encouraging. However, studies are warranted to validate our results using analgesics and pain-relieving interventions, such as nerve block on skin temperature changes.